Protective linings for apparatus subjected to considerable temperature variations



Feb. 4, 1964 H. VOGLER 3,120,247

PROTECTIVE LININGS FOR APPARATUS SUBJECTED To CQNSIDERABLE TEMPERATUREVARIATIONS Filed Sept. 15, 1960 2 Sheets-Sheet l .I Fly. 1

10L 7 ai 6 5 /I Jnvemor: //fl/VJ' V4615)? 3,120,247 s FOR APPARATUSSUBJECTED To CONSIDERABLE TEMPERATURE VARIATIONS Filed Sept. 15, 1960Feb. 4, 1964 H. VOGLER PROTECTIVE LINING 2 Sheets-Sheet 2 .7 n venfo r:H0214; 1 0625)? United States Patent 3,12%,247 PROTECTIVE LlNlN GS FGRAPPARATUS SUB- JECTED T9 CQNSIDERABLE TEMPERATURE VARLaTIONS Hans"Vogler, Winterthur, Switzerland, assignor to Sulzer Freres, SocieteAnonyme, Winterthur, Switzerland Filed Sept. 15, 196%, Ser. No. 56,243Claims priority, application Switzerland Get. 6, 195? Claims. (Cl.138-448) This invention relates to protective linings for apparatussubjected to considerable temperature variations. More particularly theinvention relates to linings for apparatus to render the latter suitablefor use in the treatment of materials which undergo temperatureVariations of a high order.

Examples of apparatus include regulating valves, heat exchangers, heataccumulators, collecting tanks, centri fugal drums, catalytic reactionchambers, steam power installation tanks, etc.

For structural reasons and possibly in order to prevent damage bycorrosion and because such apparatus must be exposed to considerablyelevated temperatures, as for example above 600 C., it is customary toconstruct such apparatus out of forged steel, stainless steel oraustenitic steel.

Such steel, however, is not always resistant to sudden or sharpvariations in temperature and on being exposed, for example, to a sharptemperature change of a high order, undergoes crack formations endingthe useful life of the apparatus involved.

Sudden temperature changes of the degree contemplated occur, forexample, on shutting down boilers as a precautionary measure at a timewhen the superheater is filled with water or again as when operating asteam power installation at pressures exceeding the critical pressure.The heat transfer from the steam to the steel walls is especially greatbecause the vapor density of the steam is so high.

Broadly stated it is a primary object of this invention to provide meansobviating the shortcomings outlined above, and additionally resulting ina number of unique functional and structural advantages.

More specifically, it is a general obiect of this invention to providemeans conductive to a lining which is very resistant to temperaturechanges of a high order and which includes parts which are not onlyeasily fabricated, but are replaceable at a minimum expenditure of time,effort and repair.

It is another important object of this invention to provide meansaffording the development of a lining resistant to temperature changesof a high order which is simple in configuration, readily removable andreplaceable by virtue of its not being directly bonded to the body inwhich said lining is incorporated.

it is a further object of this invention to provide means facilitatingthe employment of a lining resistant to temperature changes of a highorder which does not leave any part of the body to be protected,uncovered.

Still another object of the invention is to provide means envisaglng aprotective screen or sheathing, which is resistant to marked temperaturechanges and which not only protects the apparatus body, but also itsinlet and outlet conduits, ports, etc.

Still a further object of the present invention resides in the provisionof means redounding not only to a considerable structural increase inwear or strain, but also to a highly efiicacious resistance to sudden orunforseen temperature changes to which such means may be subjectedduring operation.

Other obiects and advantages of the invention will 3,120,247 PatentedFeb. 4, 1964 appear from the following description taken in connectionwith the accompanying drawings.

In the drawings:

FIG. 1 is a vertical section of a superheater provided with a protectivelining or sleeve-like sheating constructed pursuant to the invention;

FIG. 2 is an enlarged view of a section of the superheater of FlG. 1,showing the connection of the lining with the casing of saidsuperheater; and

FIG. 3 is a vertical section of a pressure reducing valve provided witha protective lining in accordance with the invention.

This invention is principally directed to linings for apparatus e.g.pressure vessels employed in treating materials undergoing temperaturevariations of a high order, which linings are composed of a materialresistant to sudden temperature changes of a high order and are furtherso constructed that its hollow interior constitutes the apparatus bodywith which the material being treated comes in contact, while its outersurface is therewith secured to the apparatus being lined by beingwelded or otherwise held to intermediate inserts such as rings which arebonded, welded or in some other manner fastened to the inner surface ofthe apparatus.

Referring in somewhat greater detail to the drawings, there is disclosedin FIG. 1 an apparatus in the form of a superheater main 1 consisting ofa thick-walled pipe section or outer shell 2, which is closed off by abottom wall or base 3 at its lower end. In the range of pipe section 2there are provided four pipe or nipple connections 4 which in theembodiment shown are at their righthand ends inserted into counter bores45! of the pipe section 2 and are rigidly connected thereto by weldingseams 5. Adjacent the left-hand ends of the pipe connections 4 are theactual heated pipes 6 carrying the working medium.

Parts 2, 3 and 4 are constructed of austenitic steel, which is sensitiveto sudden temperature changes in that under the action of sharptemperature variations it tends to crack. To protect such parts againstsharp temperature changes, protective linings or sleeve-like elements 7,8 are located in the pipe section 2 and in the pipe connections 4. Theseprotective linings are adapted to conform to the shape of the parts tobe protected and accordingly present in the instant embodiment ahollowcylindrical form, the lining 7 bein provided at its lower end witha welded-in disk 9 which serves to protect the main bottom 3 or basefrom sharp temperature virations. For the attachment of the protectivelining 7 to pipe section 2, the latter is provided at the lower end withan annular groove it} into which is inserted a weld-in ring 11consisting of two halves, which is advantageously made of the samematerial as parts 2 and 3 and which is welded to the welding seam 12connecting these parts.

In the embodiment shown in FIG. 2 the connection or means of securingthe protective lining 7 and the pipe section 2 and bottom 3 is shownenlarged. The weld-in ring 11 has a substantially rectangularcross-section and presents on its outer peripheral face a bead 4t) ofabout triangular cross-section.

During assembly of the parts, the ring 11 is so positioned that head 49lies just between the edges of parts 2 and 3 to be welded together andis fused in the welding operation. Thereby a rigid connection is ensuredof parts 2, 3 and i1 and through the groove 10 also with the lining 7.

A similar attachment is provided for at what in FIG. 1 is the upper endof the protective lining 7, but in this instance groove 10' receivingthe split weld-in ring 11' is larger than the ring in order that theprotective lining 7 can expand in length under the influence oftemperature changes. The outside diameter of the protective lining 7 isa little smaller than the inside diameter of the pipe section 2, so thatthere remains between the inside of pipe section 2 and the outside oflining 7 a space or gap which serves to inhibit the heat transferbetween the we parts.

According to the positioning of the pipe connections 4,

there are provided in lining 7 openings 41 through which the protectivenipple linings 8 of the connections 4 can project a little into the mainspace. At their other ends, i.e., facing the pipes 6, the linings 8 are,like the lower end of lining 7, provided each with an annular groove,into which split weld-in rings 13 are inserted and to which the pipeconnections 4 and seam 14 connecting the pipes 6 are welded.

To hold the linings or sleeve-shaped screen in centered positionrelative to the particular pipe connection 4, a head for each lining maybe provided similar to head 49 referred to above. Instead of beads,supporting rings of 7 round or rectangular cross-section may be employedwhich are secured in correspondingly shaped grooves of therespectivelinings. By the arrangement of the linings 7 and 8, which maybe made, for example, of any scaleresistant ferritic material, it isachieved that any sudden and sharp temperature changes of the workingmedium, which may be, for example, a gas, pulverulent or liquidsubstance, vapor, etc., flowing through the pipe or pipe connection arekept out of contact with those parts thereof exposed and sensitive totemperature changes.

FIG. 3 shows by way of example an embodiment of the invention as appliedto a superheated-steam pressurereducing valve. In the valve body 15, aprotective lining 16 is inserted from below said body and consisting ofan upper part 17 and a lower part 18 which forms the valve seat. The twoparts 17 and 18 are locked together by means of a screw thread 19. Atits lower end, the seat part 18 presents an annular shoulder 2% whoseend faces rest against ring arrangement 21, 21 of angular crosssectionwhich forms an intermediate piece according to the invention. a

The rings 21, 21' have one leg welded to the end face 24 of the valvebody '15, and the other to the end face 25 of a pipe connection 26 whichis connected with the valve body 15 through a threaded sleeve 27.Between the two end faces of the annular shoulder 29, a groove 22 isrecessed,'and the flanges remaining on both sides of the groove areconnected by lip welding 23, 23 with the other leg of the rings 21, 21resting against the shoulder 20. The Weld connections at the rings 21,21 serve only to seal the seat portion 18 in the valve housing againstthe passage of steam; they do not serve to absorb axial tractive forces.By light welding 23 and 23' it is possible easily to eX- change the seatportion 18 forming a protective lining.

The seat portion 18 and the lining'portion 17 are in the instantembodiment constructed of austenitic steel.

The inlet opening 28 of the valve body 15 is provided with a cylindricallining 29 which is secured in the same manner as the linings 8 in FlG.l. The lining 29 extends to' the left, as shown in FIG. 3, to aconnecting flange not shown. The lining 29 is cylindrical in shape, asis the case also for the'linings 8 in the embodiment shown in FIG; 1.

The valve construction is otherwise conventional. A valve spindle 3%) isguided by means of a bearing bush 31 and sealed against the escape ofsteam into the valve body 15 by means of a packing. 32. The knownpacking 32 is adjustable by means of a threaded bushing 33. At the upperend of the valve spindle 34 there is arranged a piston 34 which isguided in a cylinder 35. Above and below piston 34 apertures 36, 37 areprovided in the cylinder 35, to which are connected pressure mediumlines (not shown), through which a pressure medium is'introduced andwithdrawn, respectively, for the operation of piston 34. Cylinder isclamped by means of This is done by the threaded sleeve 27.

4 1 screws (not shown) to a flange 38 held at the collar 39 of the valvebody 15 by a spreading ring 33'.

It can thus be seen, that there has been achieved according to theinvention protective means of the type described comprising asleeve-shaped element made of a material resistant to sudden temperaturevariations of a high order and having inner and outer surfaces, theinner surface of said element defining the inner boundary body of theapparatus, the outer surface of said element being fixedly retained inpredetermined non-leaking relationship to the apparatus body, andintermediate insert means secured to and spacing said element from saidbody.

While very satisfactory forms of the invention are disclosed,modification of details is possible within the scope of the invention.The present disclosure is merely illustrative and in no wise limitingand the invention comprehends such modifications as Will fall Within thescope of the following claims.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. In combination with a vessel comprising at least two.

vessel sections joined by a weld seam, means for thermally insulatingsaid vessel from high temperature media received by the vessel, saidthermal insulating means comprising: a hollow liner, including an outersuiface,'situated within the joined vessel sections and having a shapegenerally conforming to the shape of the vessel sections, said outersurface of said hollow liner includinga groove therein running aroundthe cross-sectional periphery of said liner and adjacent the weld seam,and spacer means partially seated in said groove and welded to the weldseam, said spacer means maintaining said liner a fixed distance from thevessel.

2. Apparatus for thermally protecting a vessel, comprising: a hollowliner, including an outersurfaee situated within the vessel and having ashape generallyconforming to the shape of the vessel, said outer surfacehaving two spaced-apart grooves running around the outer surface of saidliner; two spacer rings within the vessel and welded thereto, one ringbeing partially seated in one of said grooves and the other ring beingpartially seated in the other of said grooves whereby said hollow lineris separated from the vessel by an air space, one of said grooves beinglonger axially than the ring seated therein to allow for differentialthermal expansionof said liner axially within the vessel relative to thevessel and the other said spacer 3. Apparatus for thermally insulating avessel, which is comprised of at least two vessel sections joined by aweld seam, from high temperature media received by the vessel,comprising: a hollow liner, including an outer surface, situated withinthe joined vessel sections and having a shape generally conformhig tothe shape of the vessel sections, said outer surface of said hollowliner including a groove therein running around the cross-sectionalperiphery of said liner and adjacent the weld seam,

and spacer means partially seated in said groove and welded to the weldseam, said spacer means maintaining said liner a fixed distance from thevessel, said groove being dimensionally larger than the spacer meansseated therein to permit expansion of said liner.

4. Apparatus for thermally protecting a vessel, comprising: a hollowliner including an outer surface, said hollow liner being situatedwithin the vessel and having a shape generally conforming to the shapeof the vessel, said outer surface having ,a groove running thereabout,

a spacer ring within the vessel and welded thereto, said spacer ringbeing partially seated in said groove whereby said hollow liner isseparated from the vessel by an air space.

5. A protective lining for use in a vessel subject to widely varyingtemperatures, said vessel comprising at least two vessel sectionsadapted to be joined by a welding seam, said lining comprising: at leastone sleeve element of a material resistant to sudden Widely varyingtemperature changes, said sleeve element including an inner surface andan outer surface and having a shape conforming to the shape of theinterior of the vessel, said inner surface of said sleeve elementdefining the inner wall of the vesesl when emplaced Within said vessel,said outer surface of said sleeve element including a groove runningthereabout; and, a weldable insert partially nested within said groovewhereby said sleeve element is separated from the inside Wall of thevessel by a fixed distance, said Weldable insert being situated at thewelding seam between the vessel sections whereby said insert may bewelded to the welding seam as said vessel sections are weldably joined.

References Cited in the file of this patent UNITED STATES PATENTS1,964,123 Kaiser June 26, 1934 2,497,780 Lawson Feb. 14, 1950 2,955,415Long Oct. 11, 1960 10 2,982,311 Haskell May 2, 1961

1. IN COMBINATION WITH A VESSEL COMPRISING AT LEAST TWO VESSEL SECTIONSJOINED BY A WELD SEAM, MEANS FOR THERMALLY INSULATING SAID VESSEL FROMHIGH TEMPERATURE MEDIA RECEIVED BY THE VESSEL, SAID THERMAL INSULATINGMEANS COMPRISING: A HOLLOW LINER, INCLUDING AN OUTER SURFACE, SITUATEDWITHIN THE JOINED VESSEL SECTIONS AND HAVIGN A SHAPE GENERALLYCONFORMING TO THE SHAPE OF THE VESSEL SECTIONS, SAID OUTER SURFACE OFSAID HOLLOW LINER INCLUDING A GROOVE THEREIN RUNNING AROUND THECROSS-SECTIONAL PERIPHERY OF SAID LINER AND ADJACENT THE WELD SEAM, ANDSPACER MEANS PARTIALLY SEATED IN SAID GROOVE AND WELDED TO THE WELDSEAM, SAID SPACER MEANS MAINTAINING SAID LINER A FIXED DISTANCE FROM THEVESSEL.